In the environment of general pursuit of narrow frame and large screen occupation ratio in the current liquid crystal display industry, array substrate as an important component of a liquid crystal display has become the main object of our study. A fan-out area is disposed at the edge of an array substrate, and scan signals and data signals can be transmitted to each pixel by a timing controller through wiring in the fan-out area, thus realizing the display function of the liquid crystal display.
To decrease the size of the fan-out area, a double layer of metal wiring is adopted for some array substrates to reduce the total area of the wiring in the fan-out area. That is, two metal wires are arranged in a stacked manner and both connected to the same pixel unit. But the double layer of wiring may cause a short circuit between metal lines and common electrode on the surface and cause damage to the array substrate because of the manufacturing precision of the line width, poor cutting and the like.